Method and arrangement for concreting vertical shafts

ABSTRACT

A method and an arrangement for concretizing vertical shafts having a depth of e.g. 500 m or more. The concrete is conveyed to a low-lying application site ( 20 ) in the shaft by a concrete column that is situated in a downpipe ( 30 ). Delivery of concrete is guaranteed without separation (demixing) or clogging of concrete. The concrete is removed in portions of from the succeeding concrete column at the output end of the downpipe ( 30 ), is separated from the concrete column, is depressurized and it subsequently conveyed to the application site.

CROSS REFERENCE TO RELATED APPLICATION

This application is a national stage of PCT/EP00/11329 filed Nov. 16,2000 and based upon DE 199 59 217.9 filed Dec. 8, 1999 under theInternational Convention.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention concerns a process and a device for concretizing deep,vertical shafts, wherein concrete is conveyed from above ground to alower lying application site via a cement column contained in adownpipe.

2. Description of the Related Art

Shafts, as they occur in mines, which are to be concretized inaccordance with the inventive process, have a depth of, for example, 500m and more. When the concrete is allowed to drop uncontrolled in thedownpipe, there is the danger of separation (demixing) and congestion.This applies also in the case when detours are provided within thedownpipe. The conveyance of concrete purely by gravity into such deepshafts is associated with high frictional wear, even if a series ofsliding gates are provided along the drop zone, which are periodicallyswitched. Further, the sliding gates which are conventionally availabledo not provide reliable performance due to the high frictional wearduring switching by the abrasive concrete and the large number ofnecessary switching procedures.

BRIEF SUMMARY OF THE INVENTION

Beginning therewith it is the task of the present invention to develop aprocess and a device for concretization of deep, vertical shafts, withwhich a reliable transport of the concrete to the application site isaccomplished without demixing and with the greatest possible operationalreliability.

The inventive solution is based upon the concept of a procedure in whichthe concrete is removed in portions at the outlet side of the downpipeand separated from the following concrete column, and thereby is removedfrom being under pressure, and then is conveyed or supplied to theapplication site. In order to accomplish this, it is proposed inaccordance with a preferred embodiment of the invention that theconcrete column at the outlet end of the downpipe is conveyed to acylinder, and there is supported in this cylinder by a piston, whichpiston yields, thereby increasing the cylinder volume, such that thecylinder content, after the piston reaches the piston end position, isseparated from the remaining concrete column, and thereafter preferablywith advancing of the piston is pushed out of the cylinder directly orindirectly to the application site. In the case of indirect application,the concrete is preferably conveyed to a buffer container and from thereis delivered on to the application site. The concrete which is not underpressure is preferably delivered to the application site via a furtherdrop zone, which is shorter than the concrete column, and is formed forexample by a distribution hose.

Technically speaking, the described cylinder arrangement is adecompression pump, which on its inlet side is acted upon by an upstreamconcrete column under pressure, and in which the concrete isdecompressed in portions, and only then is supplied to the applicationsite.

According to a preferred embodiment of the invention the upstreamconcrete column is redirected at the outlet end of the downpipe into anupwardly directed, downwardly open cylinder, while the concrete portionseparated from the concrete column exits downwardly from the cylinder.

In a further preferred embodiment of the invention it is envisioned thatthe upstream concrete column communicates alternatively at the outletend of the downpipe with two separate cylinders, and from these isportioned in counterstroke and then delivered without pressure, incertain cases via the buffer container, to the application site.

It is first necessary to fill the downpipe with concrete, such that nodemixing and no disruption occurs along the drop zone. In order toachieve this, the downpipe is first filled with water, before theconcrete is introduced into the downpipe with the intermediate insertionof at least one sealing element. The water reaching the outlet side isthen conveyed upwards, under the influence of the upstream concretecolumn, via a return pipe connected to the lower end of the downpipe andcommunicating therewith and preferably having a smaller diameter, or thewater is discharged into the shaft.

For carrying out the inventive process, a device for concretization ofdeep, vertical shafts is provided, comprising a filling pump positionedabove-ground and a downpipe connected to the filling pump, wherein theoutlet end of the downpipe is connectable to a pressure-tightdecompression pump, of which the outlet is in turn connectable with theapplication site. Preferably, a distribution hose leading to theapplication site and moveable by hand is connected to this outlet.

According to a preferred embodiment of the invention the decompressionpump includes a pipe switch connectable with the outlet of the downpipe,of which the pipe switch outlet is alternatively connectablepressure-tight with one of two cylinders, of which the respective othercylinder communicates with an outlet or delivery conduit, preferably viaa common buffer container, and wherein pistons are provided in thecylinder which pistons slide back and forth in opposition orcounterstroke. The pipe switch is positioned in the buffer containerbelow the downwardly open cylinders, and faces with its outlet upwardsin the direction of the cylinder openings. On the other hand, thedelivery conveyor from the decompression pump in the form of, forexample, a distribution hose faces downwards, so that the decompressedconcrete can be conveyed to the application site under the influence ofgravity. In order to be able to carry out maintenance or servicing ofthe decompression pumps without having to disengage the concrete columnfrom the downpipe, a sliding gate is provided in the downpipe ahead ofthe decompression pump.

Further, in accordance with a preferred embodiment of the invention, atthe deepest point of the downpipe prior to the decompression pump, acloseable return pipe is connected in communication with the downpipe,preferably with smaller cross section than the downpipe. The return pipeserves for removing the water filled into the downpipe prior to thefilling of the downpipe with concrete, removing the water upwards out ofthe shaft under the influence or pressure of the following concretecolumn. The water return thus occurs under the principle of thecommunicating pipes.

The invention is further concerned with a decompression pump fordelivery of thick materials under pressure, in particular concrete, toan application site, in particular for the employment in aconcretization process of the above-described type. The decompressionpump exhibits in accordance with the invention a pipe switch whichreceives at the inlet side the thick material under pressure, which pipeswitch is connectable at its outlet side alternatingly with one of twocylinders, of which the respective other cylinder is preferably incommunication with an outlet via a common buffer container, and whereintwo pistons are provided in the cylinders operating back and forth incounterstroke. The buffer container preferably includes on its floor apreferably downward facing outlet, onto which the distribution hose isconnectable. Further, the buffer container is preferably provided with apressure tight closeable servicing or maintenance opening.

With the above-described measures it is ensured that the pressureproduced in the cement column is controlled or subordinated at any depthof the shaft, and that the delivery of the concrete occurs withoutproblems. Advantageously for this purpose a control device can beprovided for synchronizing the control of the filling pump and thedecompression pump.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following the invention will be described in greater detail onthe basis of the embodiment represented in schematic manner in thedrawing. There is shown

FIG. 1 a section through a shaft with a shaft concretization device;

FIG. 2 a segment X from FIG. 1 in enlarged representation;

FIG. 3 an enlarged section from FIG. 2 in the decompression pump inpartial sectional representation.

DETAILED DESCRIPTION OF THE INVENTION

The device shown in the figure is designed for concretization of theshaft walls 10 of a shaft 12 having a depth of for example 500 m andmore. The concrete is distributed from the various platforms 14, whichcan be accessed via ladders 16, with the manually guided distributionhose 18 in freefall within the premounted shells 20, which are connectedat the floor 22. The delivery of the concrete via the distribution hose18 occurs through the outlet 24 of a decompression pump 26, of which theinlet. 28 is connected to a downpipe 30. The downpipe 30 extends fromabove ground (upper edge 31 of the shaft 12) downwards essentiallyvertically along a shaft wall 10 and is bent at the height of the loweredge of the decompression pump 26 in the direction thereof. The downpipe30 is supplied at its inlet side via a fill pump 32, so that a concretecolumn is formed in the downpipe 30, which at the end of the downpipe 30faces the inlet 28 of the decompression pump under high pressure.

The decompression pump 26 includes a pipe switch 34 in the form of anS-pipe, which is mounted to a buffer container 36 pivotably about anaxis 38 vertical concentric to the inlet opening 28 and pivotable withthe aid of a hydraulic drive 40. At the upper side of the buffercontainer 36 two delivery cylinders 42 are arranged vertically, whichwith their downward facing openings 44 communicate with the buffercontainer 36 and of which the pistons 42′ are drivable in counterstrokewith the aid of a hydraulic cylinder 46, of which the piston 42′ extendson the rod side through a water seal 47. The pipe switch 34 is drivenvia the hydraulic drive 40, synchronized with the hydraulic cylinders46, so that the outlet opening 48 of the pipe switch 34 is alternatinglypositioned in front of one of the cylinder openings, while therespective other cylinder opening 44 faces freely downwardly in thebuffer container. The hydraulic aggregate 54 for supplying the hydraulicdrive 40 and the hydraulic cylinder 46 is located on a platform 14 inthe area of the decompression pump 26. The pipe switch 34, in the caseof the downwardly driven pistons 42′ in one of the cylinders 42, ispositioned in front of the cylinder opening 44, so that the concretecolumn under pressure is supported, through the pipe switch 34, againstthe concerned piston 42′. In the withdrawal or return stroke of thepiston 42′, the following concrete column pushes into the concernedcylinder 42, until the piston 42′ reaches its upper end point. Then thepipe switch is switched to the other cylinder, of which the piston 42′is situated in its lower-most end position. At the same time the firstcylinder is opened towards the buffer container 46, so that the thereinsituated portion of concrete is freed of pressure since it is under onlythe ambient pressure existing in the buffer container 46, and uponadvancing of the concerned piston 42′, is pushed into the buffercontainer 36. From the buffer container 36 the concrete falls throughthe outlet 24 into the distributor hose 18 and is there delivered to theapplication site in freefall via the hoses 20.

The buffer container 36 is provided with a side lid 50, which can beopened for servicing or maintenance. Upstream of this, the downpipe 30is preferably blocked via a slide valve 52, in order to render the pipeswitch 34 pressure-free.

In order to be able to fill the downpipe 30 without problems, a waterconduit 56 is additionally provided, which is in communication with thedownpipe 30 in the area of the slide gate 42 and in the lower floor areaof the downpipe 30. First, while the slide gate 52 is closed, thedownpipe 30 is filled to the top via the water conduit 56. Then, whilethe slide gate 52 is still closed, concrete is filled into the downpipe30 with the interposition of at least one seal, using the fill pump 32,and the therein situated water is displaced upwards via the conduit 56under the principle of the communicating pipes. As soon as the concretecolumn reaches the vicinity of the slide gate 52, this is opened, suchthat the water located in the lower range is displaced via the followingconcrete column via the lower segment of the water conduit 56 and theconcrete column finally enters into the pipe switch 34 via thedecompression pipe inlet 28. For this, then, the decompression pump 26must be placed into operation via the hydraulic drive 40 and thehydraulic cylinders 46.

The cleaning of the device occurs via a water column, which isintroduced into the downpipe while the filling pump 32 is switched offand with the interposition of a pipeline scrapper. For this, anapproximately 20 m tall water column is sufficient, which as theoperation is resumed follows into the decompression pump 26 up onto thebuffer container 36.

In summary the following can be concluded: The invention relates to amethod and an arrangement for concretizing vertical shafts having adepth of e.g. 500 m or more. The concrete is conveyed to a low-lyingapplication site 20 in the shaft via a concrete column that is situatedin a donwpipe 30. The aim of the invention is to guarantee delivery ofconcrete free of separation (demixing) and clogging. The concrete iswithdrawn in potions from the succeeding concrete column on the outputend of the downpipe 30, is separated from the concrete column,depressurized, and is subsequently delivered to the application site.

What is claimed is:
 1. Process for concretization of deep shafts, inwhich concrete is conveyed via a concrete column situated in a downpipe(30) to a deeper lying application site (20), wherein the concrete isremoved in portions from the subsequent concrete column at the outletend of the downpipe (30), separated from the concrete column, andthereby rendered free of pressure, and thereafter is conveyed to theapplication site (20), wherein the concrete column is conveyed at theoutlet end of the downpipe (30) to a cylinder (42) and there issupported by a piston with enlargening of the cylinder volume withretreating piston, and wherein the cylinder content after reaching apiston end position is separated from the remaining concrete column andthereafter preferably with advancing of the piston is discharged fromthe cylinder (42) directly or indirectly to the application site (20).2. Process according to claim 1, wherein the concrete is conveyed fromthe cylinder (42) to a buffer container (36) and from there is deliveredto the application site (20).
 3. Process according to claim 1, whereinthe concrete rendered free of pressure is conveyed to the applicationsite via a further drop section, which is shorter than the height of theconcrete column.
 4. Process according to claim 1, wherein the followingconcrete column at the outlet end of the downpipe (30) is conveyed to anupwardly facing, downwardly open cylinder (42) and that the concreteportions separated from the concrete column are discharged downwardsfrom the cylinder (42).
 5. Process according to claim 1, wherein thefollowing concrete column at the outlet end of the discharge pipe (30)are introduced alternatingly into two separate cylinders, areproportioned thereby in counterstroke and optionally via a buffercontainer (36) are discharged to the application site.
 6. Processaccording to claim 1, wherein the downpipe (30) is first filled withwater, before the concrete is introduced with interposition of at leastone sealing element in the downpipe (30) and that the fill waterreaching the outlet side is returned upwards via a return pipe (56)communicating with the downpipe (30) or is discharged into the shaft. 7.Device for concretization of deep shafts, with a fill pump (32) and adownpipe (30) connected to the fill pump, of which the outlet end of thedownpipe (30) is connectable to a pressure tight decompression pump(26), of which the outlet (24) is connectable with an application site(20), wherein the decompression pump (26) includes a pipe switch (34) ofwhich the inlet side is connectable with the downpipe (30), of which theoutlet side is alternatingly connectable to one of two cylinders (42) ofwhich the respectively other cylinder (42) leads to the discharge (24)preferably via a common buffer container (36), wherein pistons moveableback and forth in counterstroke are provided in the cylinders (42). 8.Device according to claim 7, wherein at the outlet (24) leading to theapplication site (24) can be connected.
 9. Device according to claim 7,wherein the pipe switch (34) is provided in the buffer container (36)below the downwardly open cylinders (42) and of which the outlet sidesface upwards in the direction of the cylinder openings (44).
 10. Deviceaccording to claim 7, wherein the outlet (24) from the decompressionpump (26) faces downwards.
 11. Device according to claim 7, wherein aslide gate (52) is provided in the downpipe (30) ahead of thedecompression pump (26).
 12. Device according to claim 7, wherein thedownpipe (30) is connected prior to the decompression pump (26) to acloseable return line (56) preferably with smaller cross-section thanthe downpipe (30).
 13. Device according to claim 12, wherein the returnline (56) is directed to above ground.
 14. Device according to one ofclaim 7, whereby a control device for the synchronized controlling ofthe fill pump (32) and the decompression pump (26).
 15. Decompressionpump for conveyance of thick material under pressure, in particularconcrete, to an application site (20), characterized by a pipe switch(34) with an inlet for receiving the thick material under pressure, ofwhich the outlet side is alternatingly connectable to one of twocylinders (42) pressure tight, of which the respective other cylinderleads to an outlet (24) via a common buffer container (36), wherein twocylinders operable in counterstroke are provided in the cylinders. 16.Decompression pump according to claim 15, wherein the buffer container(36) includes a floor side, preferably downwardly directed outletopening (24).
 17. Decompression pump according to claim 15, whereby thebuffer container (36) includes a service or maintenance openingcloseable pressure tight with a lid (50).